About this utility
How to use IPv4 CIDR & Subnet Calculator
Inspect an IPv4 address and CIDR prefix without any network requests.
What to provide
Enter an IPv4 address followed by a prefix, such as 192.168.10.42/24.
- Paste, type, or drag and drop a supported text file into the input area.
- Review the input and the clearly labeled output behavior.
- Select “Run tool” or press Ctrl/Command + Enter, then copy, download, or move the result back into the first input for another pass.
What the result means
Network, mask, broadcast, usable range, and address counts.
Privacy and safety
This utility is loaded as browser code and processes your input only in this tab. OmniCastConverter has no upload endpoint and never stores your content, filenames, tokens, or secrets. Generated markup and code are shown as inert text and are never executed.
Limitations
- /31 and /32 networks are reported using point-to-point and single-host semantics; IPv6 requires a dedicated future calculator.
Try the included example
Select “Load example” at any time to restore this tested sample.
192.168.10.42/24